To improve passing topography capacity of 2WD truck on soft soil, A track device circling driving wheel (TDCDW) is developed and tested. Tests are conducted on sandy loam to determine the traction performance of the TDCDW. The drawbar pull and the slip of the 2WD truck with TDCDW are measured by the dynamometer vehicle. The soil resistance of 2WD truck with TDCDW is got by pulling the wire rope fixed on truck with the winch and reading the load cell fixed on the wire rope. The main results of this study are: The load on the front wheel has no influences on the tractive effort of TDCDW on sandy loam. The slip of the vehicles with the TDCDW is not the simple assembled slip of wheel on TDCDW and TDCDW on sandy loam. When the load is the same, the maximum tractive effort of truck with TDCDW is equal to the maximum tractive effort of tracked vehicle with the same contact area on sandy loam.